A conventional light source is schematically shown in FIG. 1. It has a plurality of light elements, such as RGB elements, 107; that is, an element that generates red light, an element that generates green light, and an element that generates blue light. When combined the light elements 107 are able to provide any desired color of the emitted light. In order to obtain a desired color, or character, typically defined as color point, of the emitted light a control system is included in the light source 101.
A main part of the control system is a light source controller 103, which calculates individual drive signals for all of the light elements 107 and feeds the individual drive signals to the individual light elements 107, and more particularly to drivers 105 thereof. This is done via a light source bus 109, where the light source controller 103 consecutively addresses the light elements 107. The power consumption of the controller is relatively high, since it is comparable to a (simple) computer that is permanently switched on.